PXF4336 Datasheet, PDF (109/425 Pages) Infineon Technologies AG – ABM Premium ATM Buf fer Manager

ABM-P
PXF 4336 V1.1
Functional Description
PHY1
LCI=a
Line card with ABM-P
VD
VS
Switch
Core
Line Card with ABM-P
VS
LCI=b
VD
PHY2
ABR VC_f
FRM_f
BRM_b
ä
FRM_b
≈
BRM_f
ABR VC_b
overflow
adjust
adjust
overflow
ABR VC_f
BRM_b
≈ ^FRM_f
ä ^BRM_f
FRM_b
ABR VC_b
ABR segment 1
No ABR Protocol
ABR segment 2
Legend:
ABR VC_f = ABR connection in forward direction
ABR VC_b = ABR connection in backward direction
FRM = forward Resource Management cell
BRM = backward Resource Managment cell
Notes:
• per-VC queues separate rates in both ABR segments
• serving rates of queues dynamically adjusted
≈ _{= Virtual Source}
= Queue with peak rate limiter
ä ^{= Virtual Destination}
Figure 3-46 Distribution of VS/VD Function in a Switch
VS/VD Options
Destination Behavior (ATM Forum TM 4.1 spec. rule 3 options): If FRM cells are received
and turned into BRM cells, while older BRM cells are still waiting for transmission, the
contents overwrite option is supported. The new BRM cell is scheduled in place of the
old BRM cell for in-rate transmission. The old BRM cell is lost.
Data Sheet
109
2001-12-17